Image processing device, image processing method, and image processing program for deciding a similarity between a captured image and a sample image

Provided are an image processing device, an image processing method, and an image processing program that can decide a user image that is similar to a plurality of model images and that follows a flow of the plurality of model images. Combinations of (I2) and (P3), (I51) and (P21), (I150) and (P49), (I198) and (P79), (I201) and (P30), (I249) and (P99), (I300) and (P101), and (I301) and (P112) in which similarities between the model images and the user images are equal to or more than a first threshold value are detected. The combination of (I201) and (P30) in which a relative time difference of the imaging time is equal to or more than a second threshold value is eliminated, and the rest combinations are second combinations. From among the second combinations, a model image group and a user image group, which are a collection of similar images, are decided, and the user images similar to the model images attached on a model album are decided from the user image group. A user album is created from the decided user images.